Wednesday marks the 16th anniversary of President Clinton's welfare overhaul. That law has become a major issue in this year's presidential campaign.

Republican Mitt Romney keeps saying that President Obama has gutted the law, even though every major fact-checking organization says the attacks are false.

Romney rolled out his line of attack two weeks ago in an ad that says: "On July 12th, President Obama quietly announced a plan to gut welfare reform by dropping work requirements. Under Obama's plan, you wouldn't have to work and wouldn't have to train for a job. They just send you your welfare check."

Since then, it's become a constant refrain in more ads and on the stump.

"How in the world could he not understand the power of work, the dignity of work?" Romney said last week in Zanesville, Ohio. "And taking work out of welfare is something I'll change. I'll tell you that — day one."

"A Mitt Romney TV ad claims the Obama administration has adopted 'a plan to gut welfare reform by dropping work requirements.' The plan does neither of those things."

"Work requirements are not simply being 'dropped.' States may now change the requirements — revising, adding or eliminating them — as part of a federally approved state-specific plan to increase job placement."

"And it won't 'gut' the 1996 law to ease the requirement. Benefits still won't be paid beyond an allotted time, whether the recipient is working or not."

Even a Republican architect of the law, Ron Haskins, told NPR: "There's no plausible scenario under which it really constitutes a serious attack on welfare reform."

Still, the accusation endures. The Republican National Committee released an ad Wednesday noting the 16th anniversary of the law, and stating: "If Barack Obama had his way, this day would have never happened."

And the Romney campaign put out a memo Wednesday repeating the claim that Obama gutted the Clinton-era welfare reforms after taking office.

So why continue beating this drum?

Partly because people believe it.

"We think that the fact that the work requirement has been taken out of welfare is the wrong thing to do," said Peggy Testa, attending a Tuesday rally near Pittsburgh for Romney running mate Rep. Paul Ryan.

When told that's not actually what had happened, Testa replied: "At this point, [I] don't know exactly what is true and what isn't, OK? But what I do know is I trust the Romney-Ryan ticket, and I do not trust Obama."

Another Romney supporter at the Ryan rally said it's really tough to know what's true anymore.

"I think we always have to look at who the fact checkers are," Ken Mohn said. "There's lots of ... groups that purport themselves to be neutral, nonpartisan, but often are [partisan]."

This specific attack about welfare ties into a broader concern that many Republicans share: Romney often argues that Obama and the Democrats are making America a government-dependent society.

Pam Malcolm, who attended a Romney rally outside of Cleveland a few months ago, agreed.

"I really don't want to help somebody who just decides, 'Oh, well, I was raised on welfare. I can raise my children on welfare,' " Malcolm said. "I had a cousin who, she is a registered nurse and the stories she told me about people coming in there and having babies just so they could get more on their food stamps and more on their welfare. It's like no, I don't want to take care of those people."

Princeton University political scientist Martin Gilens, who wrote the book Why Americans Hate Welfare: Race, Media and the Politics of Antipoverty Policy, said there's another unspoken factor in all of this.

"I do think a lot of it has to do with race," he said.

Gillens said his research shows that Americans think about welfare in a way that aligns pretty neatly with their perceptions about race. For example, whites tend to believe that most poor people are black. But actually, poor people are more likely to be white than black or Hispanic.

Gillens said it's impossible to know whether the Romney campaign decided to play into a racial strategy or whether it's an accident. But in a way, it doesn't matter.

"Regardless of what their conscious motivations are, the impact of these kinds of attacks on welfare and, in particular, on the perceived lack of work ethic among welfare recipients, plays out racially and taps into Americans' views of blacks and other racial stereotypes," he said.

Robert Rector of the conservative Heritage Foundation calls that claim preposterous.

"The left declared that welfare reform itself was racist," he said. "It's not a racial issue. It is an issue of extraordinary budgetary cost and an increasing level of dependence among all kinds of groups in our society."

Rector was co-author of a blog post on the Heritage Foundation website last month claiming that Obama "guts welfare reform."

Today is the 16th anniversary of the bipartisan welfare overhaul signed by President Clinton. The law has become a major issue in this year's presidential campaign. Mitt Romney insists President Obama gutted the law, even though every major fact-checking organization says those attacks are false.

NPR's Ari Shapiro looks at why the Romney campaign is sticking to its guns.

ARI SHAPIRO, BYLINE: Mitt Romney rolled out this line of attack two weeks ago.

(SOUNDBITE OF A POLITICAL AD)

UNIDENTIFIED MAN: Under Obama's plan, you wouldn't have to work and wouldn't have to train for a job. They just send you your welfare check.

SHAPIRO: Since then it's become a constant refrain in more ads and on the stump. Here was Romney last week in Zanesville, Ohio.

MITT ROMNEY: Going out and saying he's going to take the welfare - excuse me - the work requirement out of welfare. How in the world could he not understand the power of work, the dignity of work? And...

SHAPIRO: PolitiFact says Romney's claims are Pants On Fire Bogus. The Washington Post's fact checker awarded four Pinocchios, the top rating. And FactCheck.org reached the same conclusion that these claims are false.

Even a Republican architect of the welfare law, Ron Haskins, told NPR...

RON HASKINS: There's no plausible scenario under which it really constitutes a serious attack on welfare reform.

SHAPIRO: Still, the accusation endures. Today, the Republican National Committee released a new ad. And a memo from the Romney campaign this morning included the claim that President Obama gutted welfare. So why keep beating this drum? Well, partly because people believe what they're hearing.

Peggy Testa and her husband came to a Paul Ryan rally outside of Pittsburgh yesterday.

PEGGY TESTA: You know, we think that the fact that the work requirement has been taken out of welfare is the wrong thing to do.

SHAPIRO: I told her that's not actually what happened.

TESTA: You know. I, at this point, don't know exactly what is true and what isn't, OK? But what I do know is I trust the Romney-Ryan ticket and I do not trust Obama.

KEN MOHN: I think we always have to look at who the fact-checkers are. There's lots of groups that purport themselves to be neutral, non-partisan, but often are.

SHAPIRO: And this specific attack about welfare ties into a broader concern that many Republicans share. Romney often argues that President Obama and the Democrats are making America a government-dependent society.

Pam Malcolm agrees and it makes her furious. She went to a Romney rally outside Cleveland a few months ago.

PAM MALCOLM: I really don't want to help somebody who just decides, oh, well, I was raised on welfare, I can raise my children on welfare. I had a cousin who, she is a registered nurse, and the stories she told me about people coming in there and having babies just so they could get more on their food stamps and more on their welfare. It's like, no, I don't want to take care of those people.

SHAPIRO: Political scientist Martin Gilens, of Princeton, says there's another unspoken factor in all of this.

MARTIN GILENS: I do think a lot of it has to do with race.

SHAPIRO: Race. Gilens wrote the book "Why Americans Hate Welfare." His research shows that Americans think about welfare in a way that aligns pretty neatly with their perceptions about race. Gilens says it's impossible to know whether the Romney campaign decided to play into a racial strategy or whether it's an accident. But in a way, it doesn't matter.

GILENS: Regardless of what their conscious motivations are, the impact of these kinds of attacks on welfare and in particular on the perceived lack of work ethic among welfare recipients, plays out racially and taps into Americans' views of blacks and other racial stereotypes.

ROBERT RECTOR: The left declared that welfare reform itself was racist. It's not a racial issue. It is an issue of extraordinary budgetary cost and an increasing level of dependence among all kinds of groups in our society.